Synthesis and superior lithium storage performances of hybrid hollow urchin-like silicate constructed by nanotubes wrapped in reduced graphene oxides

Hybrid hollow urchin-like cobalt and copper silicate constructed by nanotubes encapsulated in graphene nanosheets composites were successfully prepared using graphene oxide as carrier and silica spheres as template, which were done through a well-known Stober process and a hydrothermal method. In fact, the synthesis of hybrid urchin-like silicate constructed by nanotubes through onestep hydrothermal reaction has rarely been reported. The electrochemical performances of the composites as lithium-ion battery anode materials were studiedfor the first time. As novel anode materials of Li-ion batteries, the special hollow urchin-like structure not only could facilitate the Li+ diffusion and electron transport but alsocouldaccommodate the volume variation during the conversion reactions. In addition, the introduction of graphene can make the electrical conductivity better. Graphene wrapped hollow urchin-like silicate compositespossesses superior electrochemical cycling properties. The first discharge capacity is1955.2mAh/g with a current density of 300 mA/g. The unique well-designed configuration presents a beneficial method to synthesize efficient and high performance electrode materials for advanced power applications. (C) 2017 Elsevier Ltd. All rights reserved.